Lock any app with your fingerprint
Secure Folder is a free app lock for Android. Put WhatsApp, your gallery,
messages or banking apps behind your fingerprint, PIN or pattern — then hide the locker itself
behind a working calculator, so nobody knows it is there.
Set it up in three steps
About a minute, no account needed.
- Choose your apps. Open Secure Folder and pick anything installed — chat,
social, gallery, banking. There is no limit. - Grant two permissions. Usage access lets the app notice when a protected
app opens; display-over-other-apps lets the lock screen appear above it. A guided checklist
walks you through both. - That’s it. Opening a protected app from your home screen now shows a lock
screen. Opening it from inside Secure Folder opens it normally.
Weighing up your options first? Our guide to
how to lock apps on Android covers the built-in
tools on Samsung, Xiaomi, OPPO and Pixel phones before it covers ours.
Hide the app lock behind a calculator
An app locker sitting on the home screen tells people you have something to
lock. Secure Folder can disguise its own icon as a Calculator, Weather app or Notepad.
It really calculates
The calculator disguise is a working
calculator. Anyone who opens it just does maths.
Your PIN is the key
Type your secret PIN, press equals, and the
vault opens instead of showing a result.
Four looks
Calculator, Weather, Notepad — or the plain vault
icon if you would rather not disguise it at all.
What it looks like
Your data does not leave your phone
Nothing is uploaded
Your PIN, your locked app list and every
setting stay in the phone’s private storage.
Backup is switched off
Cloud backup and phone-to-phone transfer
are disabled for this app, so vault data cannot leave even through Android’s own backup.
PBKDF2, not plain text
Your PIN is stored with key-stretching,
never as readable text.
Biometrics stay with Android
Unlocking uses the official
BiometricPrompt API. The app never sees or stores your fingerprint.
What this app does not do
It locks apps. It does not move photos into a separate
gallery and it does not encrypt files. If you need a photo vault, this is not that app — better
to know now than to be disappointed after installing.
Common questions
How do I set up Secure Folder?
Install it, add the apps you
want protected, and grant usage access plus display-over-other-apps when the guided checklist
asks. Opening a protected app then shows a lock screen needing your fingerprint, PIN or pattern.
If you would rather compare it against your phone’s built-in options first, read
how to lock apps on Android.
Can I hide an app lock behind a calculator?
Yes. Secure Folder
disguises its launcher icon as a Calculator, Weather app or Notepad. The calculator really works —
your secret PIN plus equals opens the vault.
Does an app lock work without a fingerprint sensor?
Yes. It uses whatever
screen lock your phone already has, so a PIN, pattern or password works fine — including on older
Android 8 phones with no fingerprint sensor.
Why does an app locker need device admin permission?
Device admin stops the app
being uninstalled to bypass your lock. It requests one policy, force-lock, and nothing else. It
cannot read your messages, photos, files or contacts, and it cannot wipe your phone. Switch it off
any time in Settings → Security → Device admin apps.
Is Secure Folder free?
Yes, free and ad-supported. One short video removes
pop-up ads for 24 hours and the banner for 1 hour. No security feature is ever behind an ad or a
payment.
Which Android versions are supported?
Android 8.0 and later.
Lock your private apps in under a minute
Free, no account, nothing leaves your device.
Get it on Google Play